The present invention relates to semiconductor components such as IGBTs (insulated gate bipolar transistors), diodes and thyristors having a field stop zone.
A field stop zone typically is located adjacent an n-base layer. The field stop zone thus may define two sides, with a side adjacent the n-base layer, and a side away from the n-base layer. In an IGBT, a p-type collector layer typically borders the side away from the base layer. In a modified design, the field stop zone can also be surrounded by the n-base layer. In this case, the side adjacent the n-base layer is defined as the side of the n-base layer which is farther away from the p-type collector. While the field stop zone typically is a doped area of an n material, in some semiconductor components it may be a doped area of a p material.
It is known to provide more than one dopant implant in the field stop zone, with the highest concentration implant nearest the side away from the base material.